EP1174713A1 - Method and apparatus for measuring the gas ratio in a two-phase fluid flowing in a canalisation, especially a cryogneic fluid - Google Patents
Method and apparatus for measuring the gas ratio in a two-phase fluid flowing in a canalisation, especially a cryogneic fluid Download PDFInfo
- Publication number
- EP1174713A1 EP1174713A1 EP01401843A EP01401843A EP1174713A1 EP 1174713 A1 EP1174713 A1 EP 1174713A1 EP 01401843 A EP01401843 A EP 01401843A EP 01401843 A EP01401843 A EP 01401843A EP 1174713 A1 EP1174713 A1 EP 1174713A1
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- EP
- European Patent Office
- Prior art keywords
- fluid
- sensitive
- measuring
- variations
- pipeline
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 238000000034 method Methods 0.000 title claims abstract description 4
- 239000012530 fluid Substances 0.000 title claims description 30
- 238000001228 spectrum Methods 0.000 claims abstract description 11
- 238000005259 measurement Methods 0.000 claims description 3
- 238000011088 calibration curve Methods 0.000 claims description 2
- 239000007788 liquid Substances 0.000 abstract description 10
- 239000000203 mixture Substances 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 239000007787 solid Substances 0.000 description 3
- 239000007921 spray Substances 0.000 description 3
- 238000007710 freezing Methods 0.000 description 2
- 230000008014 freezing Effects 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
- G01N29/4409—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison
- G01N29/4427—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison with stored values, e.g. threshold values
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/02—Analysing fluids
- G01N29/036—Analysing fluids by measuring frequency or resonance of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/14—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object using acoustic emission techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/024—Mixtures
- G01N2291/02433—Gases in liquids, e.g. bubbles, foams
Definitions
- the present invention relates to the measurement of the presence of two phases in cryogenic fluid pipes.
- Cryogenic equipment generally uses liquefied gases to maintain a very cold atmosphere within an application volume such as a volume of cooling, freezing or crusting.
- the heat inputs during the flow of the fluid in a pipe causes the vaporization of the fluid and the appearance of bubbles or sections of gas within the liquid.
- This phenomenon is not unfavorable up to a certain value which is around 1% by mass for conventional freezing tunnels.
- the invention aims to create a precise means of measuring the gas rate in a two-phase fluid which makes it possible to determine with a maximum of precision the proportion of gas in a liquid flowing in a pipeline cryogenic.
- the device shown in Figure 1 includes a microphone 1 disposed near a pipe through which a cryogenic fluid circulates such as liquid nitrogen, said pipe being here materialized by a spray systems liquid nitrogen spray nozzle 2 type VV65025 by example.
- the microphone 1 is connected by a cable 3 to a central acquisition unit Keithley 575 digital 4, for example.
- the acquisition unit 4 is advantageously connected to a microcomputer 6 of the PC type for example.
- the microphone When spraying liquid nitrogen through nozzle 2, the microphone detects an acoustic signal of determined frequency which varies according to the gas content of liquid nitrogen.
- the microphone signal recorded by the central acquisition unit shows the shape of the signal in Figure 2.
- FFT fast Fourier transform
- This amplitude and frequency envelope graph is produced in recording the minima and maxima of the frequency spectrum.
- Methods of obtaining the gas rate in a two-phase fluid are numerous and range from simple area-by-area comparison of surfaces obtained by integrating variables, up to modeling curves to be compared.
- the digital processing device can include means for generating a modeled graph of the frequency spectrum of the device sensitive, and means for comparing the graph modeled with a modeled standard graph corresponding to a series of standard values of the rate of gas in a two-phase fluid.
- the invention can also be applied to a measurement in pipeline closed by fitting a suitable vibration sensor such as a solid / solid microphone or an accelerometer with separate electronics, in order to measure in real time the rate of gas in a two-phase fluid generated in a pipeline transporting a cryogenic fluid for any type of application industrial.
- a suitable vibration sensor such as a solid / solid microphone or an accelerometer with separate electronics
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- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
Description
La présente invention est relative à la mesure de la présence de deux phases dans les canalisations de fluide cryogénique.The present invention relates to the measurement of the presence of two phases in cryogenic fluid pipes.
Les équipements cryogéniques utilisent en général les gaz liquéfiés pour maintenir une atmosphère très froide à l'intérieur d'un volume d'application tel qu'un volume de refroidissement, de surgélation ou de croûtage.Cryogenic equipment generally uses liquefied gases to maintain a very cold atmosphere within an application volume such as a volume of cooling, freezing or crusting.
Les entrées de chaleur au cours du cheminement du fluide dans une canalisation provoquent la vaporisation du fluide et l'apparition de bulles ou de tronçons de gaz au sein du liquide.The heat inputs during the flow of the fluid in a pipe causes the vaporization of the fluid and the appearance of bubbles or sections of gas within the liquid.
Il s'ensuit l'apparition d'un mode appelé "mode diphasique".It follows the appearance of a mode called "two-phase mode".
Ce phénomène n'est pas défavorable jusqu'à une certaine valeur qui est d'environ 1% massique pour les tunnels de surgélation classiques.This phenomenon is not unfavorable up to a certain value which is around 1% by mass for conventional freezing tunnels.
Au-delà de cette valeur, le rendement des dispositifs de dispersion de l'agent cryogénique se trouve fortement diminué.Beyond this value, the efficiency of the dispersing devices of the cryogenic agent is greatly reduced.
L'invention vise à créer un moyen précis de mesure du taux de gaz dans un fluide diphasique qui permette de déterminer avec un maximum de précision la proportion de gaz dans un liquide circulant dans une canalisation cryogénique.The invention aims to create a precise means of measuring the gas rate in a two-phase fluid which makes it possible to determine with a maximum of precision the proportion of gas in a liquid flowing in a pipeline cryogenic.
Elle a donc pour objet un dispositif de mesure du taux de gaz dans un fluide diphasique circulant dans une canalisation de fluide, caractérisé en ce qu'il comporte, disposé à proximité du courant de fluide circulant dans ladite canalisation, un dispositif sensible aux variations du son résultant du passage du fluide dans la canalisation en fonction de la teneur en gaz dudit fluide et délivrant des signaux de sortie traduisant lesdites variations, ledit dispositif n'étant pas en contact physique avec la canalisation.It therefore relates to a device for measuring the rate of gas in a two-phase fluid flowing in a fluid line, characterized in what it comprises, arranged near the current of fluid circulating in said channeling, a device sensitive to variations in sound resulting from the passage fluid in the pipeline as a function of the gas content of said fluid and delivering output signals translating said variations, said device not being in physical contact with the pipeline.
Selon d'autres caractéristiques :
- ledit dispositif sensible est relié à un dispositif d'acquisition des signaux de sortie du dispositif sensible et de conversion de ces signaux en données numériques et ledit dispositif d'acquisition est connecté à son tour à un dispositif de traitement numérique des signaux de sortie convertis en signaux numériques dudit dispositif sensible ;
- le dispositif sensible aux variations du son régnant dans la canalisation est un microphone ;
- le dispositif sensible aux variations du son dans la canalisation est un accéléromètre ;
- le dispositif de traitement numérique comporte des moyens pour générer un graphe enveloppe du spectre de fréquence du dispositif sensible par enregistrement des minima et maxima du spectre de fréquence et des moyens de comparaison de cette courbe enveloppe avec une courbe d'étalonnage du dispositif sensible ;
- le dispositif de traitement numérique comporte des moyens pour générer un graphe modélisé du spectre de fréquence du dispositif et des moyens de comparaison du graphe modélisé avec un graphe modélisé étalon correspondant à une série de valeurs étalons du taux de produit diphasique.
- said sensitive device is connected to a device for acquiring the output signals of the sensitive device and for converting these signals into digital data and said acquisition device is in turn connected to a device for digital processing of the output signals converted into digital signals from said sensitive device;
- the device sensitive to variations in the sound prevailing in the pipeline is a microphone;
- the device sensitive to variations in sound in the pipeline is an accelerometer;
- the digital processing device comprises means for generating an envelope graph of the frequency spectrum of the sensitive device by recording the minima and maxima of the frequency spectrum and means for comparing this envelope curve with a calibration curve of the sensitive device;
- the digital processing device comprises means for generating a modeled graph of the frequency spectrum of the device and means for comparing the modeled graph with a standard modeled graph corresponding to a series of standard values of the rate of two-phase product.
Rappelons qu'un accéléromètre mesure des accélérations que subissent des masses bien déterminées.Recall that an accelerometer measures accelerations that undergo well-defined masses.
Si on le positionne sur une canalisation il va retransmettre des vibrations, si on lui adjoint une membrane, il devient un microphone (selon l'approche « son » de la présente invention).If we position it on a pipe it will retransmit vibrations, if we add a membrane, it becomes a microphone (depending the “sound” approach of the present invention).
L'invention sera mieux comprise à la lecture de la description qui va suivre, donnée uniquement à titre d'exemple et faite en se référant aux dessins annexés, sur lesquels :
- la Fig.1 est une vue schématique du dispositif de mesure du taux de gaz dans un fluide diphasique suivant l'invention ;
- la Fig.2 est un graphique de l'amplitude en fonction de la fréquence du signal de sortie du microphone représentant un faible taux de gaz dans un fluide diphasique; et
- la Fig.3 est un graphique de la courbe enveloppe de la réponse en fréquence du microphone et d'une courbe étalon.
- Fig.1 is a schematic view of the device for measuring the rate of gas in a two-phase fluid according to the invention;
- Fig.2 is a graph of the amplitude as a function of the frequency of the microphone output signal representing a low rate of gas in a two-phase fluid; and
- Fig.3 is a graph of the envelope curve of the frequency response of the microphone and a standard curve.
Le dispositif représenté à la figure 1 comporte un microphone 1
disposé à proximité d'une canalisation dans laquelle circule un fluide cryogénique
tel que l'azote liquide, ladite canalisation étant ici matérialisée par une
buse 2 de pulvérisation d'azote liquide Spray Systems de type VV65025 par
exemple.The device shown in Figure 1 includes a
Le microphone 1 est relié par un câble 3 à une centrale d'acquisition
numérique 4 de type Keithley 575, par exemple.The
Au lieu du microphone, il est également possible d'utiliser un accéléromètre de faible encombrement.Instead of the microphone, it is also possible to use an accelerometer small footprint.
La centrale d'acquisition 4 est avantageusement connectée à un
micro-ordinateur 6 de type PC par exemple.The
Lors de la pulvérisation d'azote liquide par la buse 2, le microphone détecte un signal acoustique de fréquence déterminée qui varie en fonction de la teneur de l'azote liquide en gaz.When spraying liquid nitrogen through nozzle 2, the microphone detects an acoustic signal of determined frequency which varies according to the gas content of liquid nitrogen.
Le signal du microphone enregistré par la centrale d'acquisition présente l'allure du signal de la figure 2.The microphone signal recorded by the central acquisition unit shows the shape of the signal in Figure 2.
A l'aide d'un logiciel d'acquisition tel que le logiciel Viewdac, on obtient
en temps réel, par transformée rapide de Fourier (FFT), le spectre de
fréquence correspondant entre 10 et 25000 Hz qui est ensuite stocké sous
forme de fichier ASCII sur disque dur dans l'ordinateur 6.Using acquisition software such as Viewdac software, we obtain
in real time, by fast Fourier transform (FFT), the spectrum of
corresponding frequency between 10 and 25000 Hz which is then stored under
form of ASCII file on hard drive in
Un algorithme supplémentaire développé par exemple en langage Pascal permet de générer à partir du fichier précité, un graphe enveloppe représenté en trait plein gras sur la figure 2.An additional algorithm developed for example in language Pascal allows to generate from the above file, a represented envelope graph in solid bold line in Figure 2.
Ce graphe enveloppe d'amplitude et de fréquence est réalisé en enregistrant les minima et maxima du spectre de fréquence.This amplitude and frequency envelope graph is produced in recording the minima and maxima of the frequency spectrum.
On procède ensuite à un étalonnage précis du graphe enveloppe en générant au sein du liquide pulvérisé par la buse 2, du gaz à partir d'un apport d'énergie mesurable, pour pouvoir établir le taux de gaz dans le fluide diphasique présent en temps réel à la sortie de la canalisation, par mise en coïncidence du graphe en temps réel et des graphes enregistrés lors de la phase d'étalonnage comme représenté sur la figure 3.We then proceed to a precise calibration of the envelope graph by generating within the liquid sprayed by the nozzle 2, gas from a measurable energy supply, to be able to establish the rate of gas in the fluid two-phase present in real time at the outlet of the pipeline, by setting coincidence of the real-time graph and the graphs recorded during the calibration phase as shown in Figure 3.
Sur cette figure, l'enveloppe du signal à traiter est tracée en trait plein alors que la courbe étalon est tracée en trait interrompu. In this figure, the envelope of the signal to be processed is plotted full while the standard curve is drawn in broken lines.
Les méthodes d'obtention du taux de gaz dans un fluide diphasique sont nombreuses et vont de la simple comparaison zone par zone des surfaces obtenues par intégration des variables, jusqu'à la modélisation des courbes à comparer.Methods of obtaining the gas rate in a two-phase fluid are numerous and range from simple area-by-area comparison of surfaces obtained by integrating variables, up to modeling curves to be compared.
Ainsi, le dispositif de traitement numérique peut comporter des moyens pour générer un graphe modélisé du spectre de fréquence du dispositif sensible, et des moyens de comparaison du graphe modélisé avec un graphe modélisé étalon correspondant à une série de valeurs étalons du taux de gaz dans un fluide diphasique.Thus, the digital processing device can include means for generating a modeled graph of the frequency spectrum of the device sensitive, and means for comparing the graph modeled with a modeled standard graph corresponding to a series of standard values of the rate of gas in a two-phase fluid.
Les résultats obtenus permettent de mesurer le taux de gaz dans un fluide diphasique apparaissant à la sortie des rampes de pulvérisation d'azote liquide dans un tunnel par exemple.The results obtained make it possible to measure the rate of gas in a two-phase fluid appearing at the outlet of the spray bars liquid nitrogen in a tunnel for example.
L'invention peut également être appliqué à une mesure en canalisation fermée par mise en place d'un capteur de vibrations adéquat tel qu'un microphone solide/solide ou un accéléromètre à électronique séparée, afin de mesurer en temps réel le taux de gaz dans un fluide diphasique généré dans une canalisation transportant un fluide cryogénique pour tout type d'application industrielle.The invention can also be applied to a measurement in pipeline closed by fitting a suitable vibration sensor such as a solid / solid microphone or an accelerometer with separate electronics, in order to measure in real time the rate of gas in a two-phase fluid generated in a pipeline transporting a cryogenic fluid for any type of application industrial.
Claims (7)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR0009102A FR2811762B1 (en) | 2000-07-12 | 2000-07-12 | DEVICE FOR MEASURING THE GAS RATE IN A DIPHASIC FLUID FLOWING IN A FLUID PIPING, PARTICULARLY CRYOGENIC FLUID |
| FR0009102 | 2000-07-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP1174713A1 true EP1174713A1 (en) | 2002-01-23 |
Family
ID=8852393
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP01401843A Withdrawn EP1174713A1 (en) | 2000-07-12 | 2001-07-10 | Method and apparatus for measuring the gas ratio in a two-phase fluid flowing in a canalisation, especially a cryogneic fluid |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP1174713A1 (en) |
| FR (1) | FR2811762B1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2222807C2 (en) * | 2001-02-12 | 2004-01-27 | Государственное образовательное учреждение высшего профессионального образования Южно-Российский государственный технический университет (Новочеркасский политехнический институт) | Method of processing of signals of acoustic emission of generated dispersive systems |
| EP2708885A1 (en) * | 2012-09-13 | 2014-03-19 | Spirax-Sarco Limited | Method and apparatus for determining the phase compositions of a multiphase fluid flow |
| WO2016124165A1 (en) * | 2015-02-03 | 2016-08-11 | Rheinisch-Westfälische Technische Hochschule (Rwth) Aachen | Method and arrangement for analysis of a material flow |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0320280A2 (en) * | 1987-12-10 | 1989-06-14 | Exxon Research And Engineering Company | Acoustic monitoring of two-phase feed nozzles |
| US5115670A (en) * | 1990-03-09 | 1992-05-26 | Chevron Research & Technology Company | Measurement of fluid properties of two-phase fluids using an ultrasonic meter |
| US5741980A (en) * | 1994-11-02 | 1998-04-21 | Foster-Miller, Inc. | Flow analysis system and method |
-
2000
- 2000-07-12 FR FR0009102A patent/FR2811762B1/en not_active Expired - Fee Related
-
2001
- 2001-07-10 EP EP01401843A patent/EP1174713A1/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0320280A2 (en) * | 1987-12-10 | 1989-06-14 | Exxon Research And Engineering Company | Acoustic monitoring of two-phase feed nozzles |
| US5115670A (en) * | 1990-03-09 | 1992-05-26 | Chevron Research & Technology Company | Measurement of fluid properties of two-phase fluids using an ultrasonic meter |
| US5741980A (en) * | 1994-11-02 | 1998-04-21 | Foster-Miller, Inc. | Flow analysis system and method |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2222807C2 (en) * | 2001-02-12 | 2004-01-27 | Государственное образовательное учреждение высшего профессионального образования Южно-Российский государственный технический университет (Новочеркасский политехнический институт) | Method of processing of signals of acoustic emission of generated dispersive systems |
| EP2708885A1 (en) * | 2012-09-13 | 2014-03-19 | Spirax-Sarco Limited | Method and apparatus for determining the phase compositions of a multiphase fluid flow |
| US9588083B2 (en) | 2012-09-13 | 2017-03-07 | Spirax-Sarco Limited | Determining the phase compositions of a multiphase fluid flow |
| WO2016124165A1 (en) * | 2015-02-03 | 2016-08-11 | Rheinisch-Westfälische Technische Hochschule (Rwth) Aachen | Method and arrangement for analysis of a material flow |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2811762A1 (en) | 2002-01-18 |
| FR2811762B1 (en) | 2004-07-09 |
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